Automatic bilge pump



Sept. 29, 1970 ox ETAL 3,531,219

AUTOMATIC BILGE PUMP Filed March 10, 1969 2 Sheets-Sheet 1 FIG. I

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AUTOMATIC BILGE PUMP Filed March 10, 1969 2 Sheets-Sheet 2 lrral/viKf United States Patent O 3,531,219 AUTOMATIC BILGE PUMP Francis K. Fox, 3821 Nevie St., Oakland, Calif. 94601, and John W. Munce, Oakland, Calif. (14578 Tiburon Road, San Leandro, Calif. 94577) Filed Mar. 10, 1969, Ser. No. 805,427 Int. Cl. F04b 9/06, 21/02 U.S. Cl. 417-211 6 Claims ABSTRACT OF THE DISCLOSURE A self-priming pump having a double-acting piston driven by a pendulum subject to wave motion, and particularly adapted for automatic bilge pumping. An adjustable, double belt drive through fixed pulleys transmits power to the piston from the pendulum, and ball check valves control pump suction and discharge. Non-slip belt drive operates pump piston in response to slightest pendulum motion, and with equal efiiciency for a wide angle of pendulum positions.

BACKGROUND OF INVENTION A large number of prior art workers have attempted to employ wave motions for pumping action, and early examples of this type of apparatus are to be found in US. Pats. Nos. 823,431 and 836,600 to I. A. McManus. Subsequent efforts in this general field of endeavor are to be found, for example, in US. Pat. No. 1,305,509 to Weston et al. A recent improvement in the general field is briefly described and illustrated in the publication Popular Science of September 1968, at page 120 thereof.

Much of the prior art devices in this general field employ some type of pendulum which moves in response to rocking of a boat, or the like, through wave motion. By the mounting of a weight upon a pivoted level arm there is achieved a force from the shifting of the center of gravity of the weight through tilting of a boat, or the like, so that the force therefrom may be coupled in some manner to one or more pump pistons. Various defects in these prior art devices are apparent upon a close scrutiny thereof, and one of the most serious is to be found in the inability of the devices to operate satisfactorily under conditions wherein a boat within which such device may be mounted, does not move through a normal or horizontal plane.

One of the most practical applications for an automatic bilge pump is found in the field of sailing vessels, wherein powered pumping may not be readily available. Unfortunately, sailing vessels, particularly those under way, generally heel over, so that they maintain somewhat of a constant inclination to horizontal. Many pendulus devices for operating bilge pumps have been devised which require movement through a vertical plane of normal pendulum orientation. Although this may be satisfactory for an anchored sailing vessel, it is wholly inoperable for sailing vessels under way.

A further disadvantage of prior art Wave motion pumps is the inability of the pump to prime itself, and also the inability of the pump to operate efficiently under relatively small wave motions.

The present invention is particularly directed to an improved automatic bilge pump, which is equally efiicient under circumstances of large or small motions producing a pendulus action of a suspended weight, and which is completely self-priming.

SUMMARY OF INVENTION The present invention comprises what may be properly termed an automatic bilge pump in that the pump hereof operates entirely without the application of power ice from any type of motor, or the like. Furthermore, the pump operates without the necessity of priming thereof. The foregoing is achieved herein by the provision of an improved pump piston drive arrangement, and the provision of particular check valves. More specifically, there is herein provided an adjustable, double-belt piston drive from a pendulum, with the piston being arranged for double action, so that even the slightest motion of the pendulum produces a pumping action. Furthermore, the employment herein of check valve balls having a specific gravity only slightly greater than that of water, and being slightly flexible and resilient, produces perfect valve seating and immediate positive pumping action with the slightest piston motion. Although the present invention has many features in common with prior-art wave motion pumps, extensive testing has established marked superiority of the present invention over prior-art devices of this type.

DESCRIPTION OF FIGURES The present invention is illustrated as to a single preferred embodiment thereof in the accompanying drawings, wherein:

FIG. 1 is a side elevational view of a preferred embodiment of the invention partially in schematic taken in plane 1-1 of FIG. 2;

FIG. 2 is an end elevational view of the automatic bilge p p;

FIG. 3 is a sectional view, taken in the plane 33 of FIG. 1;

FIG. 4 is a sectional view, taken in the plane 44 of FIG. 3;

FIG. 5 is a sectional view, taken in the plane 55 of FIG. 2; and

FIG. 6 is a sectional view, taken in the plane 66 of FIG. 5.

DESCRIPTION OF PREFERRED EMBODIMENT Referring to FIGS. 1 and 2 of the drawing, there will be seen to be illustrated a preferred embodiment of the present invention, including an upright stand, or housing 11, having spaced apart vertical side members 12 and 13, with a shaft 14 rotatably mounted therebetween adjacent the tops thereof. A pendulum 16 depends from this shaft in the form of a weight 17 and relatively vertically disposed bar 18 secured between the weight and shaft. The weight 17 may be secured to the bar 18 by any suitable means, such as, for example, extension of the bar through an opening in the weight and nuts threaded upon the bar against the weight, as illustrated. Pumping is performed by a piston 21, slidably mounted in a generally horizontally disposed cylinder 22, as illustrated in FIGS. 3 and 4. This cylinder may be mounted upon bottom crosspieces 23 extending between the side members 12 and 13. The cylinder 22 is provided with a pair of aligned longitudinal slots 24 through the sides thereof, and a pin 26 extends through the center of the piston 21 and exteriorly of the cylinder through these slots for engagement by belt drive means described below.

The piston 21 is adapted to be reciprocated back-andforth within the cylinder, and a very small clearance is provided between the piston and cylinder 'walls with the piston having a substantial length, so as to minimize any leakage along the cylinder at the piston sides. At each end of the cylinder there are provided inlet and outlet means 28 which may take the form of plates secured to the cylinder ends.

Referring to FIG. 4, there is illustrated details of an end means 28 for the cylinder. As illustrated, th se means may be provided in the form of a plate or body 29, having a lower inlet opening 31 and an upper outlet opening 32. A cylindrical insert 33 is threaded upwardly into the lower opening 31 with an opening therethrough, and is provided with an outwardly tapering upper surface 34 forming a valve seat. Within the opening 31 there is disposed a ball 36 formed of a slightly flexible and resilient material, such as a plastic, and having a specific gravity only slightly greater than that of water. This ball 36 normally rests upon the valve seat 34 to close the opening 31, but is free to move upward under the force of suction from the pump piston 21 to open the inlet for drawing water into the cylinder 22. An upper cylindrical insert 37 is threaded vertically downward into the top opening 32 in the end plate, with an opening through such cylinder for the exit of water discharged by the pump. Within the opening 32 there is disposed another ball 38 which may be identical to the ball 36 described above, and which normally rests against a valve seat 39 formed about the opening 32 interiorly thereof, as shown. This upper opening 32 has a reduced diameter extending into the cylinder from the valve seat, and an enlarged portion on the opposite side of the valve seat to accommodate the ball 39 and allow movement of the ball away from the valve seat under pressure of water pumped by the piston from the cylinder.

It will be seen that there is thus provided inlet and outlet ball check valves at each end of the cylinder, so that piston reciprocation will alternately raise the inlet check valve ball 36 to draw water through the inlet Opening 31 into the cylinder, and return travel of the piston will seat the inlet check valve and unseat the outlet check valve ball 38 to force the water upwardly out of the discharge opening 32.

As noted above, the pump is double-acting, and the cylinder is thus provided with the same inlet and outlet means 28 at each end theerof. As shown in FIG. 1, the inlet openings 31 at opposite ends of the cylinder are connected together by appropriate piping 41, which extends by means such as a rubber hose, or the like 42, to a strainer 43 located in the bilge of a boat 44. This disposition of the inlet line 42 is only schematically illustrated in FIG. 1, and, of course, the physical location of the strainer at the end of the flexible line may be disposed as desired in the vessel, but preferably at the lowest point available, in order to minimize the amount of water than can accumulate in the bilges. The outlet openings 32 of the end plates 28 are likewise connected together through suitable piping 46 which may have a flexible discharge line 47 extending therefrom for disposition over the side of the vessel, as schematically shown in FIG. 1.

Considering now the adjustable belt drive of the present invention, reference is first made to FIGS. 2 and 5, wherein it will be seen that the rotatable shaft 14 is mounted at the ends thereof in bearings 51 and 52 carried by the uprights 12 and 13 above the pump cylinder. As previously noted, the pendulum 16 is secured to this shaft 14 at the center thereof, and this may be accomplished by any suitable means so that motion of the pendulum weight rotates the shaft. A pair of like belt wheels 53 and 54 are mounted upon the shaft on opposite sides of the pendulum bar 18. Inasmuch as these belt wheels 53 and 54 are alike, only one is described in detail, and is illustrated in FIGS. and 6. These belt wheels are mounted upon the shaft for rotation back-and-forth with the shaft and, additionally, are adjustably positioned upon the shaft with respect to angular orientation thereabout. It will be appreciated that a wide variety of different physical configurations are possible to accomplish this adjustable positioning, and in the illustrations of FIGS. 5 and 6 one such physical embodiment is shown. The wheel 54 is formed of two like discs 61 and 62, with each having a peripheral groove thereabout and a central opening therethrough for passage of the shaft 14. The relative angular orientation of the discs 61 and 62 is adjustable, as by means of a bolt 63 extending through a curved slot 64 in one of the discs 61 and threaded into the other disc 62. In addition to the relative adjustment to the angular positions of the discs of the wheel, the entire wheel itself is angularly adjustable with respect to the shaft 14. This is illustrated to be accomplished by means of a pair of blocks 66 and 67 having facing circular indentations therein for engaging the shaft 14. One of the blocks 67 is secured to the disc 62, as by bolts, and the other block is attachable to the secured block 67 as by means of bolts 68 extending through the block 66 and threaded into the block 67. With the bolts 68 loosened, the wheel may be turned to the desired angular position on the shaft 14 and the bolts 68 then tightened to clamp the blocks together on the shaft, and thus lock the wheel in desired angular relation to the shaft. The reasons for adjustability of the belt wheels will become apparent from a consideration of the belt arrangement employed herein and described below.

As previously stated, the pump piston 21 is reciprocated by a transverse d-rive pin 26 extending laterally through the center thereof and through the longitudinal slots 24 in the sides of the cylinder 22. Connection between the piston drive pin 26 and the belt wheels 53 and 54 rotated by the pendulum 16 is provided by two pairs of belts 71, 72 and 73, 74. Considering the pair of belts 71, 72, it is noted that each extends at least partially about the upper wheel 54 in separate peripheral grooves thereof. In the illustrated embodiment, the ends of each of these belts are knotted or formed with a bulbous termination and the belt is fitted in a generally radial slot 76 in the wheel disc with the end extended outwardly therefrom, so as to lock the end of the belt to the disc of the wheel. The belts then extend about and downwardly from the wheel 54, and about pulley wheels 77 mounted at opposite ends of the cylinder 22 (FIG. 1). The belts 73 and 74 are likewise connected to the wheel 53, and extend downwardly and away from each other about spaced pulley wheels 78 at opposite ends of the cylinder, but on opposite sides thereof from the pulley wheels 77. These lower pulley wheels 77 and 78 will be seen to be mounted in pairs at opposite ends of the cylinder 22 for rotation. Such mounting may, for example, be accomplished by axles such as the axle 79 of FIG. 4. The belts 73 and 74, for example, extend about the rotatable pulley wheels 78 which have their lower periphery aligned with the piston drive pin 26 and the lower belt ends are aflixed to opposite ends of a connecting plate 81 secured to one end of the drive pin. The other pair of belts 71 and 72 extend about the pulley Wheels 77 into connection with a connecting plate 82 affixed to the opposite end of the drive pin, as clearly shown in FIG. 3, for example. It will be seen that with this construction and belt connection swinging of the pendulum 16 to rotate the shaft 14 will cause the belts to reciprocate the piston 21.

It is quite important in the present invention that piston drive forces be equally and accurately applied to the pump piston from the pendulum. As set forth above, the piston is driven by pairs of belts connected to opposite ends of the piston drive pin. Inasmuch as the piston very tightly fits the cylinder it is quite important that equal forces be applied to both ends of the drive pin to prevent binding of the piston. In order to achieve high ef' ficiency pumping it is also necessary that the slightest motion of the pendulum will move the piston in the cylinder to achieve a pumping action under these circumstances. With the belts connected as described above it is possible to adjust the relative angular positions of the two discs of each pulley wheel and also to adjust the angular position of the wheel relative to the shaft 14. In this manner then the apparatus is adapted for very precise adjustment of piston drive from the pendulum.

It is to be noted that the automatic bilge pump of the present invention is adapted to be employed in a boat or the like subject to wave motion so that the pendulum swings to and fro to pivot the shaft 14 back and forth and thus reciprocate the pump piston. Under most operating conditions it is highly important that the automatic bilge pump of this invention be constructed of corrosion resistant and rust resistant material. Althrough the pendulum weight 17 may be formed of lead or the like, structural portions of the device are preferably formed of brass, stainless steel, or other hi hly stable and relatively impervious materials. This point is particularly important for the cylinder and piston of the pump itself for in many applications of the invention this portion of the device may be submerged, possibly in salt water. Even a small amount of rust may impair pump piston movement and thus care should be taken not to employ iron bolts, fittings or the like. Copper or plastic lines are preferred particularly as regards to lower portions of the device which may be under water. Insofar as the pairs of belts are concerned, it has been found satisfactory to employ nylon cord which exhibits a high strength and longevity without additional stretching after tensioning.

Considering briefly the operation of the present invention, it is first noted that same is adapted to be dis posed in a vessel or the like subject to wave motion, such as for example a sailboat. It is not necessary for the de vice to be located at the lowest point in the boat but instead it may be disposed at some convenient location such as under a forward deck or the like with the suction line 42 extending to the keel at a low point in the bilge. The strainer 43 at the inlet end of the suction line 42 has a very fine screen thereon to prevent entry of foreign matter into the pump and it is noted that the suction produced by this pump is adequate to draw water upwardly a number of feet into the pump for subsequent discharge. The outlet line 47 is then placed over the side of the was sel so that water pumped from the bilges will be discharged from the vessel.

The substantially constant motion of any body of Water of substantial size within which the boat or vessel is located will then cause the pendulum 16 to swing to and fro and this in turn will pivot the shaft 14 to move the belts and drive the pump piston 21 back and forth within the cylinder 22. An extremely good valve seating is attained by the use of the particular ball checks and a substantial seal is achieved between the piston and cylinder walls so that even very slight reciprocation of the pump piston will produce a substantial pumping action to such an extent that the pump is indeed self-priming even with a substantial suction head. As the boat or vessel rocks back and forth the pendulum swings, generally as indicated by the arrows in FIG. 1, so as to reciprocate the piston and pump water from the bilges without the application of any other external power. This, of course, is particularly desirable in the case of sailing vessels which may not have motors or the like to power a pump.

A further point of particular interest and great advantage is the ability of the present device to operate While tilted at a very substantial angle. It will be appreciated that a vessel such as a sailing vessel underway is normally heeled over to port or starboard and yet bilge pumping should continue. Even though the device as illustrated in FIG. 1 be tilted in the plane of the figure through a substantial angle, the pendulum will continue to oscillate by wave motion and to impart a reciprocating action to the pump piston even through such piston may not then be located at the center of the cylinder. Pumping action continues under these circumstances, for even the slightest movement of the piston in the cylinder causes water to be drawn into one end of the cylinder and discharged therefrom upon return motion of the piston while the reverse effect is occurring at the opposite end of the cylinder. It is particularly noted that formation of the balls of the inlet and outlet check valves from a slightly resilient material having a specific gravity only slightly greater than that of water produces a very highly efficient valving action. The check valves seat extremely well but unseat very easily under pump action.

It has been found under tests that the automatic bilge pump of the present invention is highly eflicient and does operate under the various circumstances noted above. Furthermore, tests have shown that the pump continues to operate for very extended periods of time without maintenance or inspection of any sort. This is of course highly advantageous, not only for vessels underway but particularly for vessels that are moored or anchored and are often times left unattended for long periods.

Although the present invention has been described above with respect to a particular preferred embodiment, attention is directed to the appended claims for a precise delineation of the scope of the invention.

We claim:

1. An improved automatic bilge pump comprising:

(a) a cylinder with a reciprocally mounted piston therein and both inlet and outlet ball-check valves at each cylinder end,

(b) a drive pin extending laterally from said piston through slots in opposite sides of said cyinder,

(c) inlet connections connected to a first valve at each cylinder end and outlet connections connected to a second valve at each cylinder end, whereby piston reciprocation provides suction at one cylinder end and simultaneous discharge at the other end,

(d) means for mounting a shaft for rotation above said cylinder,

(e) a weight rigidly affixed to said shaft and depending therefrom to define a pendulum, and

(f) drive belts adjustably afiixed to said shaft in spaced relation therealong and extending about pulley wheels into engagement with said drive pin on opposite sides of said piston for reciprocating said piston under the influence of pendulum motion.

2. The pump of claim 1 further defined by said ballcheck valves each having a slightly resilient ball with the specific gravity thereof slightly greater than that of water.

3. The pump of claim 1 further defined by a pair of wheels adjustably affixed to said shaft directly above said pulley Wheels and said belts extending into engagement with said wheels.

4. The pump of claim 3 further defined by each of said wheels comprising a pair of discs upon said shaft with one belt attached to each disc, and means locking said discs together in adjustable angular orientation about said shaft.

5. The pump of claim 1 further defined by said pulley wheels being rotatably mounted with the lower periphery of each aligned in a plane of the piston axis and the ends of said drive pin.

6. The pump of claim 1 further defined by the means (d) comprising upright rigid side members, lower cross members mounting said cylinder, and upper cross members extending between said side members at least as high as said shaft whereby the upper cross members are out of the way of said pendulum as same swings, even with the apparatus tilted.

References Cited UNITED STATES PATENTS 2,490,484 12/1949 Snyder l037l XR 2,493,050 1/1950 Weir 1037l ROBERT M. WALKER, Primary Examiner 

